Aspectos cognitivos na doen?a de parkinson e sua rela??o com o polimorfismo val158met da catecol-O-metiltransferase

Made available in DSpace on 2015-04-14T14:51:20Z (GMT). No. of bitstreams: 1 439240.pdf: 319940 bytes, checksum: 78e312c8115e9e5356969e795047faba (MD5) Previous issue date: 2012-02-27Although Parkinson s Disease (PD) is predominantly a movement disorder, the presence of cognitive problems related to frontal function, even in the earliest stages has been observed. These problems include attentional, executive and memory deficits. A study using an experimental paradigm developed to investigate the effects of different encoding instructions on contextual memory showed that, unlike healthy controls, PD patients could not reverse their contextual memory deficits and take any advantage of encoding instructions. However, it is unclear whether they have a memory deficit or executive dysfunction would be accountable for results. Attentional and executive deficits observed in PD patients have important implications for daily activities, mainly when patient perform concomitant cognitive and motor activities that are attention demanding. Catechol- O-methyltransferase (COMT) is an enzyme that degrades cortical dopamine. Some studies have examined the relationship between the COMT val158met polymorphism and executive function in PD patients and have found low enzyme activity, associated to met/met polymorphism- implying higher prefrontal dopamine levels- is related to worse performance. However, a recent study did not demonstrate a direct effect of COMT genotype on the executive performance. The present study aimed to characterize different cognitive parameters of patients with PD and to assess their relationship with the COMT polymorphism. In this study participated 18 patients with early disease stage PD and 18 healthy adults matched for age, gender and education. Patients were selected from a data bank of patients genotyped for COMT polymorphism. All participants completed the Wisconsin Card Sorting Test (WCST), the Stroop Color and Word Test, and dual tasking paradigm. In addition, patients completed a contextual memory paradigm. No effect of COMT val158met genotype on frontal function in patients with PD (executive function and contextual memory) was observed. A decrease in cognitive task performance under dual-tasking was observed in PD patients, by contrast to healthy controls. Relative dual-task cognitive cost was significantly greater for PD patients compared to controls in the arithmetic-walking condition. In conclusion, difficulties in performing a cognitive task while walking can be influenced by the executive/attentional load of the task.Embora a Doen?a de Parkinson (DP) seja predominantemente um dist?rbio do movimento, a presen?a de altera??es cognitivas relacionadas ? fun??o frontal tem sido observada mesmo nos est?gios iniciais da doen?a. Estas altera??es incluem d?ficits atencionais, executivos e de mem?ria. Um estudo usando um paradigma experimental desenvolvido para investigar os efeitos de diferentes instru??es codificadoras na mem?ria contextual mostrou que, ao contr?rio dos idosos, pacientes com DP n?o s?o capazes de reverter seus d?ficits de mem?ria e n?o tiram nenhuma vantagem das instru??es codificadoras. Entretanto, ainda n?o est? claro se estes pacientes t?m um d?ficit de mem?ria ou se as disfun??es executivas seriam as respons?veis pelos resultados observados. D?ficits atencionais e executivos observados em pacientes com DP t?m implica??es importantes nas atividades di?rias, principalmente quando o paciente desempenha atividades concomitantes cognitivas e motoras que requerem aten??o. A catecol- O-metiltransferase (COMT) ? uma enzima que degrada a dopamina cortical. Alguns estudos t?m examinado a rela??o entre o polimorfismo val158met da COMT e fun??o executiva em pacientes com DP e t?m observado que a atividade reduzida da enzima, relacionada ao polimorfismo, que implica em maiores n?veis de dopamina no c?rtex pr?-frontal, est? associada a uma pior performance. Entretanto, um estudo recente n?o demonstrou um efeito direto do gen?tipo da COMT no desempenho executivo. O presente estudo teve por objetivo caracterizar diferentes par?metros cognitivos de pacientes com DP e verificar sua rela??o com o polimorfismo da COMT. Neste estudo participaram 18 pacientes em est?gios iniciais da DP e 18 adultos saud?veis, pareados por idade, g?nero e n?vel educacional. Os pacientes foram selecionados de um banco de pacientes genotipados para o polimorfismo da COMT. Todos os participantes completaram o Teste de Classifica??o de Cartas de Wisconsin, o Teste de Stroop e o paradigma para avalia??o da realiza??o de tarefas simult?neas. Adicionalmente, os pacientes com DP completaram o paradigma de mem?ria contextual. N?o foi observado efeito do polimorfismo val158met da COMT sobre a fun??o frontal (fun??o executiva e mem?ria contextual) dos pacientes com DP. Os pacientes apresentaram um decl?nio cognitivo na realiza??o das atividades simult?neas, ao contr?rio dos controles. O custo cognitivo associado ? realiza??o da tarefa aritm?tica juntamente ? caminhada foi significativamente maior para os pacientes com DP, em rela??o aos controles. Em conclus?o, as dificuldades em realizar uma atividade cognitiva e motora simultaneamente podem ser influenciadas pela carga executiva/atencional da atividade

An?lise da rela??o entre o estilo de vida, aspectos cognitivos, capacidade de compensa??o cognitiva e n?veis de BDNF em idosos

Submitted by PPG Biologia Celular e Molecular ([email protected]) on 2018-09-21T12:01:19Z No. of bitstreams: 1 DAIANE_BORBA_DE_LIMA_TES.pdf: 957011 bytes, checksum: aabf702a83978ff60b063787acb5fb76 (MD5)Approved for entry into archive by Sheila Dias ([email protected]) on 2018-09-24T11:27:34Z (GMT) No. of bitstreams: 1 DAIANE_BORBA_DE_LIMA_TES.pdf: 957011 bytes, checksum: aabf702a83978ff60b063787acb5fb76 (MD5)Made available in DSpace on 2018-09-24T11:40:07Z (GMT). No. of bitstreams: 1 DAIANE_BORBA_DE_LIMA_TES.pdf: 957011 bytes, checksum: aabf702a83978ff60b063787acb5fb76 (MD5) Previous issue date: 2017-08-14Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPESIt is widely accepted that normal aging is accompanied by changes in cognitive abilities. It is also important to note that the pattern and degree of cognitive alterations in non-demented older adults is heterogeneous, with some of them showing significant impairments while others maintain relatively constant performances throughout aging. Among the factors that seem capable to modulate cognitive integrity on older age is life style. There are a number of suggestions that social, intellectual and physical activities enhance cognitive reserve and protect against cognitive decline. The mechanisms related to these benefits are still unknown, but intervention studies with older adults suggest that BDNF could be a mediator of the benefits on cognitive function induced by physical activity. However, studies on the effects of social and intellectual activities on this neurotrophin are scarce. In the present study, it were evaluated the lifestyle effects (social, intellectual and physical activities) on cognitive aspects and BDNF levels of healthy older adults. The relation between social, intellectual and physical activities, BDNF levels and neuropsychology performance (attention, working memory and executive function tests) was analyzed in a sample of healthy older adults (? 60 years old, n=58). The results showed no significant associations between social or intellectual activity levels with BDNF levels, but the group with the lowest level of physical activity had the lowest BDNF levels. Additionally, the findings did not identify consistent effects of these lifestyle components on cognitive functions. Since it is possible that the neuropsychological tests used had not enough sensibility to identify lifestyle effects on cognition, it was investigated a more sensible task: an incidental contextual memory test. Thus, it was evaluated the effect of physical activity on contextual memory of older adults (? 60 years old, n=52). It was observed that higher physical activity levels improved free recall and recognition of contextual memory. In addition, the combination of higher physical activity levels and an associative encoding instruction resulted in the better contextual memory in free recall. The results described above indicate that physical activity modulates BDNF levels and has the potential to improve cognitive reserve and cognitive performance. Additionally, the effects of intellectual and social activities are probably not sufficiently robust to be identified in transversal experimental designs of healthy older adults, especially when the subjects operate in a relatively narrow range of these lifestyle aspects.O envelhecimento normal ? acompanhado por mudan?as em habilidades cognitivas. ? importante notar que o padr?o e o grau de altera??es cognitivas em idosos n?o demenciados s?o heterog?neos, enquanto alguns apresentam preju?zos significativos, outros mant?m a performance constante ao longo do envelhecimento. Entre os fatores que parecem ser capazes de modular a integridade cognitiva no envelhecimento est? o estilo de vida. H? v?rias sugest?es de que as atividades sociais, intelectuais e f?sicas melhoram a reserva cognitiva e protegem contra o decl?nio cognitivo. Os mecanismos relacionados a esses benef?cios ainda s?o desconhecidos, mas estudos de interven??o com idosos sugerem que o BDNF (fator neurotr?fico derivado do c?rebro) pode ser um mediador dos benef?cios na fun??o cognitiva induzidos pela atividade f?sica. Entretanto, estudos a respeito dos efeitos das atividades sociais e intelectuais sobre esta neurotrofina s?o escassos. No presente estudo, foram avaliados os efeitos do estilo de vida (atividades sociais, intelectuais e f?sicas) sobre aspectos cognitivos e n?veis de BDNF em idosos saud?veis. A rela??o entre as atividades sociais, intelectuais e f?sicas, os n?veis de BDNF e a performance neuropsicol?gica (aten??o, mem?ria operacional e fun??o executiva) foi analisada em uma amostra de idosos saud?veis (? 60 anos de idade, n=58). Os resultados n?o mostraram associa??es significativas entre as atividades sociais e intelectuais e os n?veis de BDNF, entretanto, o grupo com n?vel mais baixo de atividade f?sica teve n?veis mais baixos de BDNF. Adicionalmente, os achados n?o identificaram efeitos consistentes destes componentes do estilo de vida sobre as fun??es cognitivas. A possibilidade deste resultado negativo ser uma consequ?ncia da falta de sensibilidade dos testes neuropsicol?gicos utilizados levou ? investiga??o de uma tarefa mais sens?vel: a de mem?ria contextual incidental. Desta forma, foi avaliado o efeito da atividade f?sica sobre a mem?ria contextual de idosos (? 60 anos de idade, n=52). Observou-se que n?veis mais altos de atividade f?sica melhoraram a evoca??o livre e reconhecimento de mem?ria contextual. Al?m disso, uma instru??o codificadora associativa combinada a n?veis maiores de atividade f?sica gerou uma melhora mais pronunciada na mem?ria contextual, principalmente na evoca??o livre. Os resultados apresentados nesta tese indicam que atividade f?sica modula os n?veis de BDNF e tem potencial para beneficiar a reserva cognitiva e a performance cognitiva. Adicionalmente, os efeitos das atividades intelectuais e sociais provavelmente n?o s?o suficientemente robustos para serem identificados em desenhos experimentais transversais especialmente quando os sujeitos se encontram em um intervalo relativamente estreito destes aspectos do estilo de vida

Age Effects on Cognitive and Physiological Parameters in Familial Caregivers of Alzheimer's Disease Patients.

OBJECTIVES:Older familial caregivers of Alzheimer's disease patients are subjected to stress-related cognitive and psychophysiological dysfunctions that may affect their quality of life and ability to provide care. Younger caregivers have never been properly evaluated. We hypothesized that they would show qualitatively similar cognitive and psychophysiological alterations to those of older caregivers. METHOD:The cognitive measures of 17 young (31-58 years) and 18 old (63-84 years) caregivers and of 17 young (37-57 years) and 18 old (62-84 years) non-caregiver controls were evaluated together with their salivary cortisol and dehydroepiandrosterone (DHEA) levels, as measured by radioimmunoassays and ELISA assays of brain-derived neurotrophic factor (BDNF) in serum. RESULTS:Although younger caregivers had milder impairments in memory and executive functions than older caregivers, their performances fell to the same or lower levels as those of the healthy older controls. Decreases in DHEA and BDNF levels were correlated with the cognitive dysfunctions observed in the older and younger caregivers, respectively. Cortisol at 10PM increased in both caregiver groups. DISCUSSION:Younger caregivers were prone to cognitive impairments similar to older caregivers, although the degree and the neuropsychological correlates of the cognitive dysfunctions were somewhat different between the two groups. This work has implications for caregiver and care-recipient health and for research on the neurobiology of stress-related cognitive dysfunctions

Results of the linear regressions for cognitive performance and the physiological parameters (DHEA or BDNF) in younger and older subjects.

<p>Results of the linear regressions for cognitive performance and the physiological parameters (DHEA or BDNF) in younger and older subjects.</p

Age Effects on Cognitive and Physiological Parameters in Familial Caregivers of Alzheimer's Disease Patients - Fig 1

<p>Age and/or stress effects at 8AM and 10PM based on the saliva levels of cortisol (a), DHEA (b) and the cortisol/DHEA ratio (c). The results expressed as the means ± standard error. * p < 0.05.</p

Performances (mean ± standard error) of younger and older controls and caregivers on neuropsychological tests.

<p>Performances (mean ± standard error) of younger and older controls and caregivers on neuropsychological tests.</p

Demographic and psychiatric measures (mean ± standard error) of the different age groups of controls and caregivers.

<p>Demographic and psychiatric measures (mean ± standard error) of the different age groups of controls and caregivers.</p